Systems and methods for detection of wound fluid blood and application of phototherapy in conjunction with reduced pressure wound treatment system

• US 7,947,033 B2
• Filed: 01/06/2006
• Issued: 05/24/2011
• Est. Priority Date: 04/06/1999
• Status: Active Grant

• Current Assignee: KCI Licensing Incorporated (3M Company)
• Original Assignee: KCI Licensing Incorporated (3M Company)
• Inventors: Robinson, Tim, Locke, Christopher B., Ganapathy, Premnarayan, Johnson, Royce
• Primary Examiner(s): Zalukaeva; Tatyana
• Assistant Examiner(s): Treyger; Ilya Y
• Application Number:
  US11/327,662
• Publication Number:
  US 20060173253A1
• Time in Patent Office: 1,964 Days
• Field of Search: 604/327, 604/541, 604/543
• US Class Current: 604/543
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/1468 using chemical or electrochemical methods, e.g. by polarographic means A61B5/1486 takes precedence
• CPC Class Codes: A61B 5/445 Evaluating skin irritation or skin trauma, e.g. rash, eczema, wound, bed sore
• CPC Class Codes: A61B 5/6834 using vacuum
• CPC Class Codes: A61M 1/73 comprising sensors or indicators for physical values
• CPC Class Codes: A61M 1/90 Negative pressure wound therapy devices, i.e. devices for applying suction to a wound to promote healing, e.g. including a vacuum dressing
• CPC Class Codes: A61M 1/95 with sensors for exudate composition
• CPC Class Codes: A61N 2005/0651 Diodes

Abstract

Wound fluid blood detection systems and methods are described that are operable in conjunction with reduced pressure wound treatment (RPWT) systems, as well as ancillary therapy and monitoring systems applied concurrently with RPWT systems. The blood detection monitor operates by optically characterizing the content of wound fluids to the extent of identifying percentage blood content. This identification relies upon the transmission of select wavelengths of light across a volume of wound fluid to a photo detector (connected to signal processing instrumentation) capable of quantifying the absorption characteristics of the fluid. The detection components may be implemented in conjunction with either a fluid flow conduit (i.e. the reduced pressure tubing directing fluid away from the wound dressing) or more directly in association with the materials that comprise the wound dressing positioned within the wound bed itself. In addition, the present invention is configured to operate in conjunction with blood gas monitoring systems operating with the RPWT. Finally, the components of the systems that serve to illuminate the wound bed, lend themselves to use in conjunction with illumination in discreet electromagnetic wave wavelengths suitable for the application of phototherapy.

Claims

1. A wound fluid blood detection system operable in conjunction with a reduced pressure wound treatment (RPWT) system wherein the RPWT system includes a tubular conduit for conducting reduced pressure to a wound dressing and withdrawing wound fluids from the wound, the blood detection system comprising:

a detection shunt for diverting at least a portion of a flow of said wound fluids away from the tubular conduit and into a fixed volume;

an electromagnetic (EM) wave source oriented to at least partially illuminate the fixed volume of said detection shunt wherein wound fluid is present during normal operation of said RPWT system; and

an electromagnetic (EM) wave detector positioned to be receptive of attenuated EM waves originating from said EM wave source and attenuated when passing through the fixed volume of said detection shunt, wherein the attenuation of the attenuated EM waves results from a partial and wavelength-specific absorption of waves by the components of the wound fluid and the absorption is measurable and indicative of a level of blood within the wound fluid.

2. The wound fluid blood detection system of claim 1, wherein said fixed volume is defined by a cuvette having an inlet for receiving said diverted flow of wound fluids and an outlet for returning said directed flow of wound fluids to said wound fluids flow within said tubular conduit, said EM wave source and said EM wave detector positioned adjacent an exterior of said cuvette and across a flow of said wound fluids through said cuvette.

3. The wound fluid blood detection system of claim 1, wherein said detection shunt comprises a section of EM wave translucent silicon based tubing, said tubing diverting a flow of wound fluid from said RPWT tubular conduit.

4. A wound fluid blood detection system operable in conjunction with a reduced pressure wound treatment (RPWT) system wherein the RPWT system includes an interior portion that comprises a translucent foam filter positioned within a wound bed and functioning as a filter component of the RPWT system, the blood detection system further comprising:

an electromagnetic (EM) wave source oriented to at least partially illuminate the interior portion of the RPWT system through the translucent foam filter wherein wound fluid is present during normal operation of the RPWT system; and

an electromagnetic (EM) wave detector positioned to be receptive of attenuated EM waves originating from said EM wave source and attenuated when passing through the translucent foam filter, wherein the attenuation of the attenuated EM waves results from a partial and wavelength-specific absorption of waves by the components of the wound fluid and the absorption is measurable and indicative of a level of blood within the wound fluid.

5. The wound fluid blood detection system of claim 4, wherein said EM wave source comprises at least one LED positioned adjacent said translucent foam filter and said EM wave detector comprises a solid state photo detector positioned adjacent said translucent foam filter.

6. The wound fluid blood detection system of claim 5, wherein said at least one LED and said photo detector are integrated into an illumination ring positioned adjacent an outer surface of said translucent foam filter, said illuminating ring serving to orient said at least one LED and said photo detector for optimal transmission and reception of EM waves into and out from said translucent foam filter.

7. The wound fluid blood detection system of claim 4, wherein:

said EM wave source comprises at least one light wave guide terminating adjacent said translucent foam filter and originating adjacent at least one LED remote from said translucent foam filter; and

said EM wave detector comprises a light wave guide originating adjacent said translucent foam filter and terminating adjacent a solid state photo detector remote from said translucent foam filter.

8. The wound fluid blood detection system of claim 7, wherein said RPWT system includes a tubular conduit for conducting reduced pressure to a wound dressing and withdrawing wound fluids from the wound, said tubular conduit comprising conduit walls, said conduit walls integrating said light wave guides for said EM wave source and said EM wave detector.

9. A wound fluid blood detection system operable in conjunction with a reduced pressure wound treatment (RPWT) system, wherein the RPWT system includes a tubular conduit having an inner volume and conduit walls for conducting reduced pressure to a wound dressing and withdrawing wound fluids from the wound, the blood detection system comprising:

an electromagnetic (EM) wave source having at least one light wave guide integrated into the conduit walls, the light wave guide having a first end oriented to at least partially illuminate the inner volume of the tubular conduit where wound fluid is present during normal operation of the RPWT system and a second end for receiving EM waves originating adjacent at least one LED remote from said tubular conduit; and

an electromagnetic (EM) wave detector having a light wave guide integrated into the conduit walls, the light wave guide having one end positioned generally opposite of said EM wave source for receiving attenuated EM waves originating from said EM wave source and attenuated when passing through the inner volume of the tubular conduit, and a second end for transmitting the attenuated EM waves terminating adjacent a solid state photo detector remote from the tubular conduit, wherein the attenuation of the attenuated EM waves results from a partial and wavelength-specific absorption of waves by the components of the wound fluid and the absorption is measurable and indicative of a level of blood within the wound fluid.